vipsthumbnail now uses vips_resize()

it used to have its own copy of this code
This commit is contained in:
John Cupitt 2015-05-09 12:54:50 +01:00
parent ec52d1b922
commit 9ea012f737
2 changed files with 29 additions and 121 deletions

View File

@ -1,6 +1,7 @@
7/5/15 started 8.1.0
- add vips_premultiply(), vips_unpremultiply()
- change the alpha range rules for vips_flatten() to match vips_premultiply()
- vipsthumbnail uses vips_resize() rather than its own code
4/5/15 started 8.0.2
- fix a refcount error in C++ wrapper, thanks huskier

View File

@ -65,6 +65,8 @@
* - exit with an error code if one or more conversions failed
* 20/1/15
* - rename -o as -f, keep -o as a hidden flag
* 9/5/15
* - use vips_resize() instead of our own code
*/
#ifdef HAVE_CONFIG_H
@ -94,7 +96,7 @@ static char *output_format = "tn_%s.jpg";
static char *interpolator = "bilinear";
static char *export_profile = NULL;
static char *import_profile = NULL;
static char *convolution_mask = "mild";
static char *convolution_mask = "none";
static gboolean delete_profile = FALSE;
static gboolean linear_processing = FALSE;
static gboolean crop_image = FALSE;
@ -159,25 +161,16 @@ static GOptionEntry options[] = {
{ NULL }
};
/* Calculate the shrink factors.
*
* We shrink in two stages: first, a shrink with a block average. This can
* only accurately shrink by integer factors. We then do a second shrink with
* a supplied interpolator to get the exact size we want.
*
* We aim to do the second shrink by roughly half the interpolator's
* window_size.
/* Calculate the shrink factor, taking into account auto-rotate, the fit mode,
* and so on.
*/
static int
calculate_shrink( VipsImage *im, double *residual,
VipsInterpolate *interp )
static double
calculate_shrink( VipsImage *im )
{
VipsAngle angle = vips_autorot_get_angle( im );
gboolean rotate = angle == VIPS_ANGLE_D90 || angle == VIPS_ANGLE_D270;
int width = rotate_image && rotate ? im->Ysize : im->Xsize;
int height = rotate_image && rotate ? im->Xsize : im->Ysize;
const int window_size =
interp ? vips_interpolate_get_window_size( interp ) : 2;
VipsDirection direction;
@ -203,42 +196,8 @@ calculate_shrink( VipsImage *im, double *residual,
direction = VIPS_DIRECTION_HORIZONTAL;
}
double factor = direction == VIPS_DIRECTION_HORIZONTAL ?
horizontal : vertical;
/* If the shrink factor is <= 1.0, we need to zoom rather than shrink.
* Just set the factor to 1 in this case.
*/
double factor2 = factor < 1.0 ? 1.0 : factor;
/* Int component of factor2.
*
* We want to shrink by less for interpolators with larger windows.
*/
int shrink = VIPS_MAX( 1,
floor( factor2 ) / VIPS_MAX( 1, window_size / 2 ) );
if( residual &&
direction == VIPS_DIRECTION_HORIZONTAL ) {
/* Size after int shrink.
*/
int iwidth = width / shrink;
/* Therefore residual scale factor is.
*/
double hresidual = (width / factor) / iwidth;
*residual = hresidual;
}
else if( residual &&
direction == VIPS_DIRECTION_VERTICAL ) {
int iheight = height / shrink;
double vresidual = (height / factor) / iheight;
*residual = vresidual;
}
return( shrink );
return( direction == VIPS_DIRECTION_HORIZONTAL ?
horizontal : vertical );
}
/* Find the best jpeg preload shrink.
@ -246,19 +205,22 @@ calculate_shrink( VipsImage *im, double *residual,
static int
thumbnail_find_jpegshrink( VipsImage *im )
{
int shrink = calculate_shrink( im, NULL, NULL );
double shrink = calculate_shrink( im );
/* We can't use pre-shrunk images in linear mode. libjpeg shrinks in Y
* (of YCbCR), not linear space.
*/
if( linear_processing )
return( 1 );
else if( shrink >= 8 )
/* We want to leave a bit of shrinking for our interpolator, we don't
* want to do all the shrinking with libjpeg.
*/
if( shrink >= 16 )
return( 8 );
else if( shrink >= 4 )
else if( shrink >= 8 )
return( 4 );
else if( shrink >= 2 )
else if( shrink >= 4 )
return( 2 );
else
return( 1 );
@ -326,17 +288,16 @@ thumbnail_open( VipsObject *process, const char *filename )
static VipsInterpolate *
thumbnail_interpolator( VipsObject *process, VipsImage *in )
{
double residual;
VipsInterpolate *interp;
double shrink = calculate_shrink( in );
calculate_shrink( in, &residual, NULL );
VipsInterpolate *interp;
/* For images smaller than the thumbnail, we upscale with nearest
* neighbor. Otherwise we make thumbnails that look fuzzy and awful.
*/
if( !(interp = VIPS_INTERPOLATE( vips_object_new_from_string(
g_type_class_ref( VIPS_TYPE_INTERPOLATE ),
residual > 1.0 ? "nearest" : interpolator ) )) )
shrink <= 1.0 ? "nearest" : interpolator ) )) )
return( NULL );
vips_object_local( process, interp );
@ -448,72 +409,18 @@ thumbnail_shrink( VipsObject *process, VipsImage *in,
return( NULL );
in = t[2];
shrink = calculate_shrink( in, &residual, interp );
shrink = calculate_shrink( in );
vips_info( "vipsthumbnail", "integer shrink by %d", shrink );
if( vips_shrink( in, &t[3], shrink, shrink, NULL ) )
return( NULL );
in = t[3];
/* We want to make sure we read the image sequentially.
* However, the convolution we may be doing later will force us
* into SMALLTILE or maybe FATSTRIP mode and that will break
* sequentiality.
*
* So ... read into a cache where tiles are scanlines, and make sure
* we keep enough scanlines to be able to serve a line of tiles.
*
* We use a threaded tilecache to avoid a deadlock: suppose thread1,
* evaluating the top block of the output, is delayed, and thread2,
* evaluating the second block, gets here first (this can happen on
* a heavily-loaded system).
*
* With an unthreaded tilecache (as we had before), thread2 will get
* the cache lock and start evaling the second block of the shrink.
* When it reaches the png reader it will stall until the first block
* has been used ... but it never will, since thread1 will block on
* this cache lock.
*/
vips_get_tile_size( in,
&tile_width, &tile_height, &nlines );
if( vips_tilecache( in, &t[4],
"tile_width", in->Xsize,
"tile_height", 10,
"max_tiles", 1 + (nlines * 2) / 10,
"access", VIPS_ACCESS_SEQUENTIAL,
"threaded", TRUE,
NULL ) )
return( NULL );
in = t[4];
/* If the final affine will be doing a large downsample, we can get
* nasty aliasing on hard edges. Blur before affine to smooth this out.
*
* Don't blur for very small shrinks, blur with radius 1 for x1.5
* shrinks, blur radius 2 for x2.5 shrinks and above, etc.
*/
sigma = ((1.0 / residual) - 0.5) / 1.5;
if( residual < 1.0 &&
sigma > 0.1 ) {
if( vips_gaussblur( in, &t[5], sigma, NULL ) )
return( NULL );
vips_info( "vipsthumbnail", "anti-alias, sigma %g",
sigma );
in = t[5];
}
if( vips_affine( in, &t[6], residual, 0, 0, residual,
"interpolate", interp,
NULL ) )
return( NULL );
in = t[6];
vips_info( "vipsthumbnail", "residual scale by %g", residual );
vips_info( "vipsthumbnail", "resize by %d", shrink );
vips_info( "vipsthumbnail", "%s interpolation",
VIPS_OBJECT_GET_CLASS( interp )->nickname );
if( vips_resize( in, &t[3], 1.0 / shrink,
"interpolate", interp,
NULL ) )
return( NULL );
in = t[3];
/* Colour management.
*
* If we've already imported, just export. Otherwise, we're in